No voltage on power rail V3
â–¶ How to fix
Check the power supply and connectors to DCU. Check the fuse. Check if other systems have similar DTCs, that would indicate a general problem in the vehicle.
What you'll see
Door functionality is limited or completely missing.
System reaction
The DCU signals 'Major fault' over CAN to MBS, which then requests 'Door malfunction' notification and an exclamation mark indication in the related door in Bus stop page in ICL.
Diagnostic depth
Detection
The DCU has detected that the voltage of power rail V1 is below 5V.
Possible cause
The reasons could be: - a fuse for the DCU in the electric centre is blown - unplugged connectors - damaged cable harness - faulty or drained batteries